[BUG] Claude in Chrome: permission_required for all MCP navigations, approval popup never renders (Windows, claude.ai)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

OS: Windows 11 Home ARM64
Extension version: 1.0.72
Using: Claude.ai web (not Claude Code CLI)

Every navigate call from the MCP returns permission_required: <host> for all domains, including benign ones like example.com. The approval popup that should allow adding hosts to the allowlist never renders, making it impossible to grant permissions and unblock navigation.

What Should Happen?

When a navigate call is made to any domain, an approval popup should appear asking the user to allow or deny access to that host. Once approved, navigation should proceed normally.

Error Messages/Logs

{"error": "permission_required", "host": "example.com"}
// Same response for every domain attempted

Steps to Reproduce

1. Open Claude.ai in Chrome with the Claude in Chrome extension installed
2. Start a Cowork/MCP session
3. Ask Claude to navigate to any URL (e.g. https://example.com)
4. Observe: navigate returns permission_required: example.com
5. Observe: no approval popup appears anywhere in the browser
6. There is no way to add the host to the allowlist

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

N/A (using Claude.ai web)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Related issues: #56965, #57219, #53630